串并联混合动力系统自适应模式切换优化控制

Optimal Control of Adaptive Mode Transition for Series-Parallel Hybrid Power System

摘要:

为改善某新型串并联插电式混合动力系统双电机纯电动至并联驱动模式切换品质，同时确保不同车辆行驶状态及驾驶员输入下模式切换策略的适应性能，提出了平顺性起机和动力性起机概念，设计了自适应模式切换优化控制策略。首先，建立该串并联混合动力系统动力学模型，并对其双电机纯电动至并联驱动模式切换过程进行分析，确定模式切换不同阶段控制目标及控制策略；其次，以车辆驾驶平顺性和发动机起动时间为优化指标，通过动态规划求解发动机最优拖转转速曲线，提出一种发动机起动模型预测优化控制策略，在线计算离合器滑摩转矩以拖转发动机跟踪目标最优转速曲线，并通过电机补偿输出端转矩波动。离线仿真及硬件在环台架试验结果表明，所开发的自适应模式切换控制策略能够满足不同的驾驶需求，并具有较好的驾驶平顺性。

Abstract:

In order to improve the switching quality of the dual-motor electric mode to parallel hybrid mode transition process of a new series-parallel hybrid power system， and ensure the adaptability of the mode switching strategy in different vehicle driving states and driver input， two mode switching control strategies of smooth starting and dynamic starting were proposed. First， the dynamic model of the series-parallel hybrid system was established， and the mode switching process from electric mode to parallel hybrid mode was analyzed to determine the control objectives and control strategies in different stages of mode switching. Then， taking the vehicle driving comfort and engine starting time as the optimization indexes， the optimal engine cranking speed curve was solved through dynamic programming， and an engine starting model predictive optimization control strategy was proposed to calculate the clutch friction torque online. The engine tracked the target optimal speed curve， and the torque fluctuation at the output was compensated by the motor. The results of the simulation and hardware in loop bench test show that the two mode switching control strategies can meet different driving requirements and have good a driving comfort.